Circuit interrupter



R. C. DICKINSON ETAL Oct. 19, 1954 CIRCUIT INTERRUPTER 3 Shee'ts-Sheet l Filed May 26, 1951 4 u INVENTORS Robert C. Dickinson and wlTNEssl-:s: I

Russell E. Frnk,

' ATTORNE Oct. 19, 1954 R. c. DlcKlNsoN ETAL CIRCUIT INTERRUPTER 3 Sheets-Sheet 2 Filed May 26, 1951 d n s 3. 0mm E r M m. F N g El VkE .I T A 4 8 3 9 O mm T .S Y CSN UY 6 :2v f .WUR 211V. l l l I IIL I l l l I I I l Ilm lD I.||||| I l l l .Il am 6 5 8 2 2 5. o 8 O O 6 6 2 A v W 5 2 O 3 3 3 2 n.. 5 5 .w 5 8 3 3 l f z 3 YH .I 5 5 6 ||I.|\\In\ P @WAI 9 4 2 2 B l 45 3 6 f f v O .b. 4 6 E 2 2 3 3 S..

Oct. 19, 1954 R. c. DlcKlNsoN E1- AL CIRCUIT INTERRUPTER Filed may 26, 1951 3 Sheets-Sheet 5 vda 0G30 l sql INVENTORS Rqbert C. Dickinsop and Issell E. Fnnk. a ATTORN WITNESSES:

Patented Oct. 19, 1954 l unirse iss-mms Param or Fic-'E ,CIRCUIT IN TERRUPTER L'Robert C; Dickinson and Russell Frink; Pittsburghy Pa.,assignors to Westinghouse Electric iCorporation; East PittsburghiP-afa `corpora- -tionzof `Pennsylvania .".App1ica,tionMay"26, 1951;v Serial No. 228,446

' 71.Claims. (013200-147 p1 2 'This'inven'tion relates tocircuit interrupters'in Incation taken in conjunction withthedrawings, general; and', more particularly; to arc-extinguishinv/high; ing structures therefor. Figure' 1 is avertical sectionalY view` throughj a In United Statespatent application-SerialNo. circuit interrupter embodying our invention; the

"720,165, led Januarywi,` 1947;'now U. S.-'Pate11t 5 lcontact structure vbeing showninthe closed" cirv2, 'i16;00'7, vissued Octoberi28, 11952,150 RobertC. cuitposition;

-Dickinson and Russell E. Frink,-entitled "Circuit Figr2 is a vertical sectional'view takenalong 1interrupter.and assigned to the'assigneeof the the-line II-II ofFig. 1;

instanty application, there'is disclosediandclaimed 'Figx-S; isa vertical sectionalvievvtaken along an air'breaketype'of circuit interrupter utilizing lcgthe line'III-III of Fig; 1; -a'substantially Hfshaped"magnetfwhichis ata `Fig.`4 is a topplan view ofeour vimproved'cirfloatingpotential. This* H--shaped magnetfwhen cuitinterrupter;

energized, serves to'l forcetwofportions `off'the "Figf is-an enlargedfragmentary;plan view in establishedarcupwardly into apair of'stacks of lsection; taken generally along the' line V-L'V of 'insulating plates. -A Atransfer interrupting stack 15" Fig. 1;A and,

is utilized to interrupt' the "transfer arc-Which Fig. 6 is an enlarged elevationalview of a transbridges the transfer-arc horns associated'withl the fer are horn.

- Hf-sha-ped-magnet, Referring to the drawings, and more particu- "One improvement 'which We-havel made'over lally to Fig. l thereof, .the reference numerall 1*the-circuit interrupterdescribed' inthe aforesaid 20 generally designates an arcchute comprising a lpatent'is-fin thearrangementv forventing thearc pair of serially related stacks ofarc extinguishgases from the transfer stack. Irrthe' aforesaid 'ing' plates 2, separated by a generally H-shaped `patent; venting ofthe arc gasesWas-provided for "magnetS disposed` at a float-ing potential. Apair by cutting windows -in the-sidewalls ofthe arc 'of serially related energizing coils'd, 5 serve, when y'chute and-letting'the'arc' gases from'thei trans- 25 energized, totsetupa magnetic field Within 'the lferstackvent laterally-outofthe arc-chute. 'Our -1nagneti3- "ASSOeiated Withthe energizing COilS *improved'venting `arrangement: constitutesl less "i, 5 ale'a pair 0f transfer are hOInS 5L T, the trans- `of ahazard to-personnel, and avoids the'possibil- Yfer areL between which is, extinguished .Within a "ity'of'flash-over*between adjacent^poles, Awhich "'transfer'nterrupting stack, generally designated i.are"generally'placed closely together. 30 by the'reference numeral, andmorei fully de- "It is-a general-object of our invention to'im- SCribedhereinafter.

" prove the interrupting'structuredisclosed inthe 'Contact structure is provided to close the cirnaforesaidpatent, cuit through the interrupter. The Contact strucft is. amore specific'objectof'our'invention to "tureSrincludesa relatively stationary contact it, `provide animprovedfventing arrangement' for the 35"'Wheh' may have a Slight lateral motion to Dror-'arc-*gasesA generatedwithin the transfer. interrupt- Vide' eentaCt DleSSllleyand aiCOODelatng movable ing stack. contact Il positioned at the outer extremityof a It is a furtherobject of ourinvention'- to so conrotatable Contactarm l2, .Operatedvby any suitgure the sidepoiey plates Aofthemagnet asv to ablemechanism, which forms no'partof our incause the several portions ofthe established varc 40"Venti0n A line COnneetOn `I3 tmay be made. to

f to rise upv wif-,hm the two-stack assemblies at Subthe. stationary contact structure' Land the other stantially the same rate of speed,l so thatmore efline Connection i4y vmay be made t0 the rotatable fective` and efficient utilizationA is' made of. both @Ontaet arm l2 in the `manneI1 indicated inFig- 1Y ,stack assembliessimultaneously. F0110Wing Operation 0f 'the Onta-et Opening Stura further object is toproyidean improved 45 "mechanism thermovable contact' H movesle'ftmethod of assembling the component parts f a Wardly away from 'the stationarycontact `i0 to circuit interrupter of theforegoing typek so .that establish .an vare therebetween. TBecausesofthe .manufacture and assembling `operationsmay be ,loop circuit including the Substantially horizontal rendered more economical and rapid. Iline connections I3,' IIL and the movable contact `Another object is to provide a meansfor pre- 50 `arm I2, the establishedarc .IEidrawn therebetween venting .magnetic forces from Vchangingthe conwill tendtobow upwardly. Due tothe proximity "ngurationoftheblowout coils, and todothisina of the depending pole portions I6, ,the magnetic simpliedand eife'ctive'manner. ux surrounding the establishedarc i5 .WilLbe "Further objeetsand advantages will readily be- 'distortedthereby "Thus,Y theiiuxabove. the arc come apparent upon reading the following speci- 55 l 5 Will pass through the depending pole portions I6 and through the yoke or centrally-disposed core I1 of the magnet 3. The magnetic ux below the arc I5 will merely pass through the air space. Consequently, since the flux below the arc I5 has a greater ux density than the ilux density in the air above the arc I5 (the flux above the arc I5 having passed through the magnet structure 3), the arc I5 will be magnetically urged upwardly into contacting engagement with the transfer arc horns 6, 1.

We provide a plurality of spaced slotted ceramic plates I8 associated with the transfer interrupting stack 8, and more clearly disclosed in Figs. l and 2. With particular attention being directed to Fig. 2, it will be observed that each refractory plate I8 has a slot I9 provided therein, the upper closed end 20 of which is laterally displaced to one side of the center-line 2| of the plates. The plates I8 are assembled alternately, as shown in Fig. 2, with the closed ends 20 thereof alternating about the center-line 2|, that is, the closed end 2 of one plate being to one side of the center-line 2|, and the closed ends 20 of the immediately adjacent plates I8 being disposed to the other side of the center-line 2 I. The resulting construction provides a Zig-zag are passage 22, as indicated in Fig. 2 of the drawings.

When the moving contact II has arrived at the position IIb in Fig. 1, the arc extending between it and the stationary contact I may consist of three portions. namely, |a, |512 and lic. The transfer arc portion I5b extends between the transfer arc horns 6, 'I and is extinguished within the transfer interrupting stack 8. This causes an energization of the two serially related blow-out coils 4, 5 surrounding the yoke or central Core I1 of the H-shaped magnet 3, as shown more clearly in Fig. 2 of the drawings.

It will be observed that the depending pole portions I8 extend downwardly below the lefthand interrupting stack 2A, whereas there is no, or relatively little, pole plate portion below the right-hand extinguishing stack 2B. Thus, the transverse magnetic field just below the interrupting stack 2A is more intensified than the transverse magnetic field just below the interrupting stack 2B. The reason for this is that normally the arc portion I5c, which is closer to the interrupting stack 2B, tends to rise up within the stack 2B faster than the arc portion Ic, which is initially drawn farther away from the interrupting stack 2A. However, for most effective operation of the interrupter as a whole, it is desirable to have both arc portions I5a, I5c move upwardly at the same rate of speed within the extinguishing stacks 2A, 2B.

By the particular conguration of the depending pole plate portion I6, as shown in Fig. l, the magnetic field is intensified just below the extinguishing stack 2A and thereby accelerates the upward travel of the arc portion |5a within the stack 2A so that its position and speed upwardly within the extinguishing stack 2A approximates that of the arc portion |5c upwardly within the extinguishing stack 2B.

Each extinguishing stack 2A, 2B includes a plurality of spaced ceramic or refractory plates 24, which more clearly are shown in Fig. 3. Each plate 24 has a closed slot 25 extending upwardly therein, the upper closed end 26 thereof being laterally displaced to one side of the center-line 21 of the plates 24. Preferably, the refractory plates 24 are spaced from each other by sections of asbestos rope 28, or narrow spacing strips, and cemented thereto to form a unitary stack assembly, which may be bodily placed downwardly within the interrupter I and rested upon the upper ends 29 of a pair of ceramic arc shields 3i). The arc shields 3|! provide an entrance portion upwardly into the arc chute I and have lug portions 3| integrally formed therewith which extend through openings 32 provided in the insulating rectangularly-shaped arc-chute jacket 33, as more clearly shown in Figs. 2 and 3 of the drawings.

To prevent the gas pressure generated within the extinguishing stacks 2A, 2B from blowing the stacks 2A, 2B completely upwardly out of the arc chute I, retainer strips 34 are provided within the arc chute jacket 33 at the upper end thereof, as indicated in Fig. 4 of the drawings. Preferably, bolts 35 are utilized to maintain the retainer strips in position.

The transfer arc horns 6, 1 are of identical construction, and Fig. 5 indicates an enlarged side-elevational view of one of them, say transfer arc horn 5. It will be observed that the lower end is curved around, as at `35, to form an arc horn for the transfer stack 8. The upper portion 31 of the arc horn `(i serves as an arc horn for interrupting stack 2A. Likewise, the transfer arc horn 1 has an upper portion thereof 38, which serves as an arc horn for the interrupting stack 2B. Cooperating with the stationary contact Iii and connected thereto by a strap connector 39 is an arc horn 4G. Disposed above the arc horn 4t is a barrier plate 4I which, as is the case with the arc horn 4|), is suitably secured to a pair of insulating plates 42 by suitable means, not shown.

Similarly, disposed at the outer end of the circuit interrupter I is an arc horn 43, above which is a barrier plate 44 secured by suitable means, not shown, to a pair of plates 45. Spacer strips 23 space the stacks 2A, 2B away from the arc horns 40, 43.

Each transfer arc horn 6, 1 has a laterally extending lug portion 45 (Fig. 6) which extends through a slot 41 provided in each side wall of the insulating arc chute jacket 33. Also, each transfer arc horn 6, "I has connected therewith a lug portion 48 which serves, as shown in Fig. 5, to laterally space insulating rectangularly-shaped washers 49 surrounding the yoke or core I1. A washer 49 is disposed immediately adjacent each blow-out coil 4, 5. Thus, it will be evident that there is provided within our improved arc chute a pair of venting passages 50 (Fig. 5), each of which is defined by a pair of the washers 49, the yoke |1 and the inner side of a transfer arc horn 6, 1. There results a distinct advantage inasmuch as there is a ready means of escapement of the arc gases generated within the transfer interrupting stack 8.

In the aforesaid patent, such gases were forced to move laterally out of windows provided in the side walls of the arc-chute jacket, In our present improved construction, these gases are readily transmitted upwardly through the pairs of venting passages 50, and upwardly out of the arc chute I.

It will be observed that not only are the washers 49 maintained laterally apart against the magnetic forces exerted by energizing the blow-out coils 4, 5 by the lugs 48 associated with the transfer are horns S, 1 but also the upper notched ends 5I of the plates I8 of the transfer interrupting stack 8 serve to maintain the washers 49 apart, as more clearly shown in Fig. 2.

' T5 'IYhelplates. I 8 vare inserted into slotsi 52, :provided inthe-upper-ends of the-arc shieldsll. 'LT-he .two coils \4,`. are electrically connected `together at .the upper ends `thereof byv the terminallflea'ds .53;54 and-a connecting bolt 5I. "Consequently,

both coils-fi, 5 are Iin* series electrically-between the transferarc horns'lt, 1.

ITheoperation of rour improved .interrupting .devicedsas follows: 'The movable' contact I I iflrst l:moves toward .theleftVas viewed 1in Fig.' 1,-?,tovthe :position: IIa. Thearc I5 is established between it and the stationarycontact l0. .'Thearc I5.is affected by. the'ldepending pole. plate Aportions I5 l :of thet magnet. 3, and .moves .upwardly into; en- .gagement :with the .transfer .arc horns 56,11; i-.Meanwhiie,..rthe"movable contact I Izzmovesto Lthe positionz I flb. The arc then consists of .three :portions I5a, 15b and. I5c..indicatedinf`Fig.; 1. T'I'he -.arc portion' I 5b .is interruptedwithin .the :transfer; interrupting stack. 8, thereby` energizing.. the-.i serially related blow-out coils\4,5, and providing atransverse magnetic eldacross the pole.' plates 55,-, said magnetic field being,particularlyxinten- A sive, due to the configuration ofY the platefportion I6, within the left-hand*arc-extinguishingg Stack 2A.

-T'he left-hand end of the arc `portion 15a transfersv to the arc horn 43, and the right-hand f end ofthe arc portion I5c transfers to therighthand arc horn 4t. The two arcyportionszwithin: -.the respective extinguishing stacks-2A,.l2kl3r1nay then be respectively designated by the reference characters 56, 5l', as indicated in Fig. 1. Each arc pontionzf 56,'51strises' upwardly within .the stacks 2A, 2B at'substantially the same rate of speed, and is forced upwardly within the zig-zag arc passages 58 provided by the 4several plates- 24` proi vided in the-extinguishing stacks 2A, 2B. AThese -ifarc portions55,57 are quicklyextinguished` at fthe upperf ends 26 of the slots 25' provided in ther. *'plates`124, and the circuit through the interrupter JI is broken.

Preferably, to -preventl the transfer archorns 6, I from being shorted by the pole plates 55, and thereby snorting out the serially related blow-out coils 4, 5, we provide an insulatingiish fipaper'strip* 59 between `eachpole plate 55, and the side of the arc chute jacket 33. Each insulating plate 59 has a slot 59a provided therethrough (Fig. 5) to accommodate the yoke I'I, so that the latter may abut against the side of the pole plates 55. These fish paper strips 59 merely have to provide insulation between the pole plates 55 and the transfer arc horns B, 1 suincient to withstand the reactance voltage of the blow-out coils 4, 5 in series. Since this is a small voltage, the insulation provided by s uch strips 59 is sufficient.

To maintain the pole plates 55 rigidly in position, a pair of bolts 60 extend completely through the arc chute I immediately inside of the inner bends of the blow-out coils 4, 5, as indicated in Figs. l and 2 of the drawings.

To assemble the arc chute, the arc shields 30 are first put into position. Then follows the insertion of the transfer arc plates I8 within the slots 52. Then follows the transfer arc horns 6, l, the blow-out coils 4, 5 with the side walls of the arc chute jacket 33 pressed outwardly sufficiently far to enable the lug portions 46 of the transfer arc horns 6, 'I to be forced through the slots 41 of the are chute jacket 33. The yoke I1 may then be placed in position, and then the extinguishing stacks 2A, 2B, together with the arc horns 40, 43.

'Ehen ifollows :tithe insulating strips H53, a and 'flastlyrftheasideepolaplatesi55. The boltsl-Bllxmay 1'. .thenzbeiinserte'd .tof-rigidly! lfholdfthea assemblyin xt position.

6, 'Iff effectively shield iany I.passage of #the gases generatediwithin the' :transfer stack .1 8' from .passv.ing through the extinguishingstacks`y 2A,2B. This featurek is lvery impor-tant for lthe,..proper functioning ofathefinterrupter. .\Also,1byl the proper configuration 1 and .disposition-of lthe-f depending.l pole-.f portions l I6 :.of' the. fpolef platesj 55, we have provided.; af substantially Vequal. upward velocity; of .travel of. the;arc iportions. 55;.51.' within the respective extinguishing. stacks '.i 2A, i 2B. By. theprovision ofithe venting.'.passages 59,1.the operation.; of. .the transf er. .interruptingista'ckc 'is rendered. more effective. i'IIhe. absence loda-#satture, it is to be clearly .understood-.that thesame was merely for thev purposeof illustration,..and that changes and modifications'. may readily be made .thereinby those skilled inlthexartpwithout departing from the spirit fand scopeiof .thexap- ,pendedclaims.

-We claim. as our invention:

l. A circuit :interrupter .including lcontact structure having a. relativelyf stationary; contact .and a cooperable-movable'scontact, the: movable contact being separable from the-relatively 4stationary1contact= yto Lestabli'shganfzarc, ',assubstan- .tially H-shaped magnet :assembly including a pair `of magneticfpole plates` and` anfinterconnecting core, a pair.:ofLextinguishing:structuresfon opposite sides of;theicoreyone.:disposedgrimmef diately adjacent'thef relatively; stationary contact ,45

.- subdividing :the :initially-.formed :are :finto two and. the other more:fremoteitherefrom;means for serially-related ,arcuporltions, fonezarc .lportion'lmovr. ing :into one extinguishingstructure and the other arc portion moving into the other extinguishing structure, and the magnet assembly having depending pole plate portions associated with the more remote extinguishing structure so that the arc portions will move within the two extinguishing structures at substantially the same rate of speed.

2. A circuit interrupter including a substantially H-shaped magnet assembly having a yoke portion, a pair of extinguishing structures disposed on opposite sides of the yoke portionl a blowout winding about the yoke portion, a pair of transfer arc horns connected to the blowout winding, a transfer arc interrupting device, means for establishing an arc, and means providing one or more venting passages between the extinguishing structures extending along the yoke portion freely venting the arc gases from the transfer are interrupting device to the ambient region exterior of the circuit interrupter.

3. A circuit interrupter including a substantially H-shaped magnet assembly having a yoke portion, a pair of extinguishing structures disposed on opposite sides of the yoke portion, a'

pair of blowout windings about the yoke portion, a. pair of transfer arc horns connected to the blowout windings, a transfer arc interrupting device, means for establishing an arc, means for spacing the blowout windings laterally apart, and the space between the blowout windings forming a pair of venting passages on opposite sides of the yoke portion extending along the yoke portion from the transfer arc interrupting device to the region exterior of the circuit interrupter.

4. A circuit interrupter including an arc chute having an insulating casing, a pair of openings in the side walls of the casing, a substantially H- shaped magnet assembly having a yoke portion, a pair of extinguishing structures disposed on opposite sides of the yoke portion, a pair of blowout windings about the yoke portion, a pair of transfer arc horns having lug portions extending through the side openings in the casing and connected to the blowout windings, a transfer arc interrupting device, means for establishing an arc, means including the transfer arc horns for spacing the blowout windings laterally apart, and the space between the blowout windings forming a pair of venting passages on opposite sides of the yoke portion extending along the yoke -portion from the transfer arc interrupting device to the region exterior of the circuit interrupter.

5. A circuit interrupter including contact structure having a relatively stationary contact and a cooperable movable contact, the movable contact being separable from the relatively stationary contact to establish an arc, a substantially H-shaped magnet assembly, a pair of extinguishing structures, one extinguishing structure being disposed immediately adjacent the relatively stationary contact and the other disposed more remote therefrom, and the magnet assembly having asymmetrically depending pole plate portions providing the magnetic circuit with a lower reluctance adjacent the entrance to the extinguishing structure more remote from the relatively stationary contact than the entrance to said one extinguishing structure.

6. A circuit interrupter including a substantially H-shaped magnet assembly having a yoke portion, a pair of extinguishing structures disposed on opposite sides of the yoke portion, a blowout winding about the yoke portion, a pair of transfer arc horns connected to the blowout winding, a transfer arc interruptingdevice at one end of the pair of arc extinguishing structures, each of said arc extinguishing structures being vented at the other end thereof, means for establishing an arc adjacent the transfer arc interrupting device, and a venting passage extending between the pair of arc extinguishing structures along the yoke portion freely venting the arc gases from the transfer arc interrupting device to the ambient region externally of the interrupter adjacent the other end of the pair of arc extinguishing structures.

7. A circuit interrupter including a substantially H-shaped magnet assembly having a yoke portion, a pair of extinguishing structures disposed on opposite sides of the yoke portion, each of said arc extinguishing structures comprising a plurality of plate-like portions of insulating material having spaces therebetween through which arc gases may pass, said yoke portion having a height several times its thickness with its height extending in the same direction as the greatest dimension of plate-like portions, yan elongated blowout winding about the yoke portion, means for establishing an arc adjacent one end of the pair of arc extinguishing structures, and a venting passage extending between the pair of arc extinguishing structures along the yoke portion in the direction of its height and extending from the end of the pair of arc extinguishing structures at which the arc is established to the other end thereof.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,398,982 Tritle Dec. 6, 1921 1,590,402 Aalborg June 29, 1926 1,606,808 Riley Nov. 16, 1926 1,713,229 Hewlett May 15, 1929 1,872,387 Baker et al Aug. i6, 1932 2,276,859 Nau Mar. 17, 1942 FOREIGN PATENTS Number Country Date 369,740 Great Britain Mar. 31, 1932 

